Molding, shaping, and uniting apparatus



Feb. 27, 1945. R. J. NEBESAR MOLDING, SHAPING AND UNITING APPARATUS Filed Aug. 29, 1942 Patented Feb. 27, 1945 MOLDING, s'HAPING, AND UNITING APPARATUS Robert Nebesar, Bristol, Va., assignor' to liniversal Moulded Products Corporation, Bristol, Va., a corporation of Delaware Application August 29, 1942, Serial No; 456,648

1 Claim.

This invention relates to improved vapparatus forl shaping, molding or uniting materials such as veneer boards, etc., into molded articles or parts. In particular,` the invention relates to apparatus for use in the quantity production of articles molded and shaped from wood veneer sheets under fluid pressure with a thermo-plastic or thermo-setting adhesive.

In operation, after sufficient vacuum hasI been established under the blanket, the whole unit is placed inside an operating chamber where the It is well known that the'production of molded wooden veneer articles under iluid pressure bonded with thermo-setting or thermo-plastic adhesives has been done in pressure tanks using collapsible alrand Water-tight containers, the interior of which is connected by relief means to the open air.

The procedure heretofore followed is, however, unsatisfactory for quantity production since the use of such containers is necessary; their loading is a lengthy procedure, and so is their deposit into the pressure tank. For bulky objects, great precautions must be taken not to damage the collapsible containers, which must sometimes be put around complicated shapes without much stretching in order to maintain absolute tightness. Furthermore, the adjustment of the relief means leading from the interior of such containers is also a lengthy and risky procedure resulting in a great amount of faulty processing and rejections.

It is the purpose of the present invention to facilitate a reliable quantity production of molded articles, and to provide suitable apparatus for on top of or made integral with platforms of the thickness required to withstand the same external uid pressure. 4 l

The platform is preferably of rounded shape with grooves provided on its vertical edges;e A collapsible, impervious blanketl can be placed over the structure to be molded, the mandrelfand the top of the platform. The blanket sides may be secured initially in the circumferential grooves of the platform edge by means of rubber or wire bands.

The upper face of the platform is connected with the under side, which is provided with valve means and a suitable nipple `for connection to the vacuum pump. The platform may also be provided with caster wheels for easy handling.

molding are established. i f

The accompanying drawing illustrates a preferred embodiment of the' invention in which:

Figure l is a plan view of a molding platform in accordance with this invention, showingl a mandrel positioned thereon;

Figure '2 is a side view of the structure shown in Fig. 1;

Figure 3 is a detail view, partly in section, showing the 7material to be molded and the impervious blanket in position;

Figure 4 is a detail view of the vacuum reservoir and connections; and

Figure 5 is a detail sectional view showing modified means for initially securing the impervious blanket to the platform.

As shown in the drawing the molding platform I is provided with casters 3; a vacuum reservoir or chamber 5 secured to its under side and sealed by gasket 9; circumferential 'grooves Il in its vertical sides or edges; intersecting channels I3 on its upper face; and a, valve controlled conduit I5 communicating with the channels I3 and vacuum chamber 5.

A mandrel or form I'I is positioned upon the upper face of the platform I, reinforcing members or struts I9 for the object being molded are desired pressure andtemperature necessary for `inserted in channels provided for that purpose in the mandrel, and the veneer sheet 2|, which with the struts I9 has been treated with a suitable thermo-plastic or thermo-setting adhesive,v

is laid over the struts and mandrel.

A flexible, impervious blanket 23 of, for example, rubber, is now placed carefully over the veneer sheet 2 I, in position upon the mandrel I1, and the entire platform I. The edges of the blanket 23 are secured in the grooves I I by means of elastic cords or Wire bands 25 so as to form a relatively air-tight seal.

The nipple 'I secured to the vacuum chamber 5 is then connected to a suitable source of vacuum, as a vacuum pump, and the chamber 5 and space beneath the blanket 23 evacuated valvesl 8 and I0 opening under the pressure differential so established. Atmospheric pressure will now force the blanket 23tightly upon the mandrel and platform, conforming it exactly to the shape of the article being molded and forcing the blanket tightly into the grooves II to form a perfectly air-tight seal, as shown in Fig. 3. Any necessary adjustments can now be made by hand.

pair of angle irons 21 are welded together, edge' to edge, and secured to the lower face of the table I along the edge thereof to form an upwardly opening channel 29 extending completely around the table I which in this case may be of any* desired shape, as rectangular,l oval, etc. y

A channel member 33 is adapted to be secured to one of the angle irons 21 vby machine screws 35, as shown in Fig. 5, and when so secured substantially closes the channel 29.

The blanket 23 -is attached tothe platform I by placing the tube 3l in the channel 29, securing the channel 33 in place, and inflating thetubeA through one or more tire valves of conventional type (not shown). The inflated tube is retained in the channel 29 and so secures the blanket in the position shown in Fig. 5. When the air ls exhausted from beneath the blanket, through nipple 1, atmospheric pressure forces the blanket 23 into the channels II, and an air-tight seal is effected.

What I claim and desire to protect by Letters Patent is:

Apparatus for use in shaping materials comprising a portable platform having an upper surface adapted to receive a forming mandrel, an impervious blanket and means for securing said impervious blanket to said platform so as to cover the upper surface thereof, said means including an'inatable tube formed at the free edge of said l blanket, a channel adapted to receive said tube `-said channel being supported from and extending Y peripherally around the platform, means for at least partially closing said channel to retain said tube within lthe channel when inflated, a vacuum v.conduit adapted to be connected. withausource .of .vacuum, and channels providing communication between the upper surface of said platform `and said vacuum conduit.

ROBERT J. NEBESARL 

